My next port of call arose as a fishing village on the banks of the Amstel in the 12th century. From central station, Amsterdam, I make my way to Het Schuim bar-gallery. Fred van Leeuwen (The Netherlands Cancer Institute) meets me for a brief chat on his way home from the lab. “You know I just talked to the Queen of Holland,” he chirps. Fred explained to the Queen that he works on budding yeast, the kind used to make the beer we’re now sipping. The Queen was impressed to learn that yeast could be helpful in the fight against human cancers. “For example, a few years ago we found an enzyme that methylates histones in yeast. A few months later a homologue was found in mammalian cells.” I ask him about this enzyme. The gene for the enzyme is called DOT1. The DOT1 enzyme methylates a specific lysine within a histone protein. “Just recently a paper came out showing that this enzyme is actually bound to a protein that is made in certain leukaemias and is involved in the misregulation of gene expression. So a finding in yeast was used to identify a protein in mammals that has now been shown to be involved in leukaemia,” Fred comments. These proteins when bound result in too much methylation on this histone. Halting this process could help to arrest the development of leukaemia.